"Everyone joins together in a ringing denunciation of so-and-so's character" is something I've seen in fic (admittedly it's often not well-earned) but not, as far as I can remember, in an actual show, and Kristy's dad SO deserved that denunciation. HE should be the one putting this much effort into salvaging his relationship with his daughter, rather than relying on Kristy to forgive and try again and again!